There may have been a second sun in our solar system

Our Sun may have already had a twin companion, astronomers have suggested – like Tattooine’s “binary” stars in Star Wars.

Harvard researchers have said that another sun was present during the formation of the solar system and could explain features such as a cloud of debris at the edge of our solar system.

The discovery could shed light on events such as the arrival of water on our planet and even the extinction of dinosaurs, the researchers believe.

It could also fill the gaps in Planet Nine, the hypothetical body that scientists say may be lurking on the edge of our solar system.

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Scientists believe the Oort Cloud was formed from debris left behind by the formation of the solar system and its neighbors, where objects were scattered by planets over great distances and some were swapped between stars.

But if the Sun had once had a binary “twin,” it would be easier to understand how the cloud formed, said Amir Siraj, an undergraduate student at Harvard, one of the study’s authors.

He said: “Previous models have struggled to produce the expected ratio between scattered disk objects and external Oort cloud objects.

“The binary capture model offers significant improvement and refinement, which is apparently evident in retrospect: most Sun-like stars are born with binary companions.”

Understanding the formation of the Oort cloud could give scientists important information about the history of life on Earth, the researchers said.

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“Objects in the Outer Oort Cloud may have played an important role in Earth’s history, such as eventually providing water to Earth and causing the dinosaurs to become extinct,” Siraj said.

“Understanding their origins is important.”

Binary stars are better at attracting and capturing debris (like the material that formed the Oort Cloud), according to Harvard’s Avi Loeb.

Loeb said: “If the Oort cloud formed as observed, it would imply that the Sun actually had a similar mass companion which was lost before the Sun left its birth cluster.”

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The researchers said the binary star would have disappeared early in the history of the solar system and could now be almost anywhere.

Siraj said: “The Sun’s long lost companion could now be anywhere in the Milky Way.

“Before the loss of the binary, however, the solar system would have already captured its outer shell of objects, namely the Oort Cloud and the population of Planet Nine.